The principle difference between the hplc and gas chromatography?

Answer 1

Thin Layer Chromatography is able to give you information based on thevisible attribute of the separated component. This information has limitations due to the mechanisms by which it is obtained. Typically the TLC plate or TLC paper is stained in order to highlight the components or observed under UV light. Visual attribute include relative spot size, intensity, and permeation distance. Results must be measured manually and often differ from analyst to analyst.

High Performance Liquid Chromatographymeasures the visible or UV absorption of the separated components. Advanced equipment using a photo diode array detector can collect absorption data at different wavelengths which is vital in determining peak purity and impurity separation. Using HPLC component data can easily be quantified manually or automatically using software coupled to the instrument. This allows for much more accurate and reproducible resultswith a degree of precision that can not be achieved using TLC. Lastly, HPLC is very fast. The main draw back is the price of instrumentation, software, and maintenance.

Answer 2

Thin layer chromatography's advantages over Column Chromatography:

* Apparatus is smaller (TLC just needs a 2 by 0.5 inch glass plate) * Quantity of material required is lesser * Faster procedure * Above points make the over all procedure cheaper

* The combinations of solvents that can be used is more * The Rf value can be measured easily, once a suitable visualizing technique (like an iodine gas chamber for carbohydrate mixtures) is used * All these makes it better suited for analytical purposes (but not for separation purposes which is actually one of its disadvantages)

Answer 3

The time required for separations vary less for HPLC than GC. High pressure is used in HPLC. Length of the column is small. GC is used for only volatile compounds mainly and only 15% of organic compounds are volatile but in HPLC both volatile and non volatile compounds are analyzed.

Answer 4

GLC is basically the same as HPLC except GLC is done with a liquid stationary phase and gaseous mobile phase. HPLC has a solid stationary phase and liquid mobile phase.

So your sample in GLC is a gas...this means you either have to heat it or it has to be volatile. Which is problematic as heat tends to destroy things (especially not good if you're using GLC to find out what your sample is...) and of course not everything is volatile.

Meanwhile, HPLC has neither of these problems.

Answer 5

gas chromatography is rapid and inexpensive.

Answer 6

In HPLC, the carrier is liquid while in GC, the carrier is gas.